Safety tackle-block.



UNITED STATES PATENT OFFICE.

ARTHUR U. BOUOHAltD, F MILWAUKEE, WlSCONbIN, ASSIGNUR TO THE FIRM OF BOUGHARD & KILLIAN, OF MILWAUKEE, WISCONSIN.

SAFETY TACKLE-BLOCK.

Specification of Letters Patent.

Patented Dec. 29, 1908.

Application filed September 12, 1908. Serial No. 452,762.

To all whom it may concern.

Be it known that I, Anrncn C. Boucnnnn, residing in Milwaukee, m the count r of Milwnukcc and State of \Visconsin, rave invented new and useful Improvements in Safety ilackle-Blocks, of which the following is a description, reference being bad to the accompanying drawings, which are a part of this specification.

This invention has for its object to pro- 1 vide a tackle block particularly designer for the purpose of lowering life boats and the like and being capable of automatically disengaging from the bio boat as soon as the weight of the latter is relieved therefrom on.

striking the surface of the water.

Another object of the invention is to accomplish such disengagement by means of spring actuated parts which will nornmlly be free from tension or con'lpression, the motion of one of the )ulleys during the initial movcment of the cvice serving to store energy in the spring means for the desired purpose.

Another object of this invention is to accomplish the disengagement by a wide 1 throw of the engaging hooks which will prevent the possibility of the suspended device hanging thereto.

Another object of the invention. is to accomplish the wide spreading movement of the engaging hooks by means of a spring actuated rack meshing with rock teeth on the j hook members.

\Vith the abov and other objects in view the invention consists in the safety tackle block herein claimed its parts and combinations of parts and all equivalents.

Referring to the accompanying drawings in which like characters of reference indicate the same parts in the different views Figure 1 is a front elevation of a safety tackle block constructed in accordance with this invenlion 3 and, Fig. 2 is a transverse sectional view thereof.

In these drawings 5 and 6 indicate a pair of sheaves mounted on pins 7 in their respce tive casings 8 and 9, the two sheave casings being adapted to fit together and the casing 1 about the sheaves in the usual manner. Each of the sheave casings has a pair of A hoistlng rope 12 enters the casing and 1s reeved l downwardly extending lugs 13 at its lower end and between each pair of lugs is pivotally mounted a hook member 14, the two hooks being opposed so as to constitute sister hooks for engaging the supporting eye l or loop 15 on the life boat or other article to I be supported. The sheave casing 9 has a pair of integral projections extending into the central space between the two sheave casings, one of them constituting a guide bearing 16 for a spindle or rod 17 which slidably passes therethrough and through the bottom of the flange 10, and the other projection constitutes a stationary nut 18 in which a screw thread 19 of the spindle works to cause said spindle to slide up or down according to the direction of its rotation. A bevel gear 20 is splined on the spindle 17 so as to be capable of turning the same, though free to slide thereon so as to permit the spindle to move longitudinally without all'ecting the position of the bevel gear. This bevel gear bears against the guide lug 16 and projects through slots in the sheave casings 8 and 9, meshing with a bevel pinion 21. carried by the sheave 6 and preferably integral therewith as shown. Thus the turning of the sheave 6 by the movement of the rope 12 thereon causes the bevel gear 20 to turn the spindle, which by working its thread if) in the stationary nutlS is moved longitudinally as well.

A double rack 22 is slidably mounted on l the lower end of the spindle 17 beneath the casings and is held thereon b a locked nut 23. Segmental racks or racr teeth 24 are formed u on or carried by the hooks 14 and mesh wit 1 the rack teeth of the double rack 22 so that a downward movement of the latter will cause the hooks to swing upon their pivotal connections and spread apart to the position shown by dotted lines in Fig. 2. A coil s )ring surrounds the lower part of the spindle 17 and bears at one end against l a shoulder 26 on said s indie and at its other end against the doube rack 22, the latter being rcferably recessed at 27 to receive the end of the spring to permit of the necessary 1 compression thereof, though the parts may be so proportioned as to dispense with the necessity or such recess. A short coil spring 28 surrounds the upper part of the spindle 17, resting upon the bearing lug 16, and is adapted to be engaged by a flange 29 on the 1 upper end of the spindle which is preferably removable therefrom for the purpose of assembling the parts.

In operation, the turning movement of the spindle caused by the movement of the rope, as above described, feeds it downwardly so as to compress spring 25 between the shoulder 26 and the double rack 22, which does not move at this time owing to the sister hooks 14 being held together by the weight of the life boat on the loop 15. The compression of spring 25 continues until the thread 19 has passed entirely through the stationary nut member 18, when the further turning of the sheave does not affect the parts. Upon the boat striking the water, and consequently relieving its weight from the loop 15, the spring 25 is capable of asserting itself by forcing the double rack 22 downwardly and thereby swinging the sister hooks apart to the position shown in dotted lines in Fig. 2, where there is no possibility of the loop 15 hanging therefrom. Before the spindle 17 completed its downward movement the flange 29 thereof engaged the spring 28, so that after the release of the sister hooks the spindle is still pressed upwardly by said spring 18 to cause the reengagemcnt of the t read 19 with the nut 18 when the reverse movement of the sheave 6 takes place upon raising the tackle block again. \Vhen the spindle has been restored to its upper positlon by this return movement, and in the meantime has drawn the double rack 22 up with it to close the sister hooks, the further turning of the pulley 6 has no effect upon the parts as the screw 19 has passed entirely through the nut member 18. The weight of the spindle 17 will be suflicient to cause the thread 19 to again engage the nut member 18 upon the pulley being turned in the direction for lowering the boat.

What 1 claim as my invention is:

1. A safety tackle block, comprising a casing, a sheave therein, a hook on the casing for engaging the object to be moved, a rack, a spring bearing thereon, teeth on the hook engaged by the rack for causing the hook to disengage from the object when relieved of the weight thereof, and means operated by the sheave for compressing the spring.

2. A safety tackle block, comprising a cas ing, a hook on the casing for engaging the object to be moved, a sheave in the casing, a spindle geared to the sheave to be turned thereby, a screw and nut connection for the spindle to give it longitudinal motion as the result of its rotary motion, a rack loosely mounted on the spindle, teeth on the hook engaging the rack, and a spring on the s indle bearing on the rack to be eompresser by the longitudinal movements of the spindle for causing the rack to throw the hook out of engagement with the object to be moved when relieved of the wei ht thereof.

3. A safety tackle bloc comprising a easing, a sheave therein, a spindle slidably and rotatably mounted in the casing, means for gearing the spindle with the sheave, a screw and nut connection between the spindle and the casing for feeding the spindle longitudi- H nally, a double rack loosely mounted on the spindle, a pair of sister hooks pivotally connected to the casing, rack teeth on the sister hooks meshing with the teeth of the double rack, and a coil spring surroiuniing and engaging the spindle and bearing on the doui lo rack, said spring being adapted to be compressed by the longitudinal movements of the spindle for causing the double rack to throw the sister hooks apart when relieved of the weight of the object supported thereby.

4. A safety tackle block, comprising pair of casings having sheaves mounted therein, a flange on one casing for engaging the other casing to space the casings apart, means for securing the casings together, a bearing lug and a l'eed nut projecting from one oi the casings, a spindle slidably and rotatably mounted in .the bearing lug and passing through the flange ol' the casing, a screw thread on the spindle engaging the feed nut, a bevel gear splined on the spindle and hearing on the bearing lug and projertinginto the casings, a bevel pinion on one of the sheaves meshing with the bevel gear. a recessed double rack slidably mounted on the spindle, a pair of sister hooks pivotaily mounted on the casings, rack teeth on the sister hooks engaging the rack teeth of the double rack, a shoulder on the spindle. a coil spring surrounding the spindle with one end. bearing against said shoulder and the other end entering the recess of the double rack, a nut threaded on the spindle for engaging the double rack, a spring surrounding the spindle and bearing on the bearing lug, and a shoul der carried by the spindle for engaging the last mentioned spring.

5. A tackle block, comprising a casing, a sheave mounted therein, means on the casing lor engaging the object to be moved, and automatic means operated by the movements oi the sheave for causing the engaging means to become disengaged from said object.

6. A tackle block, comprising a casing, a sheave therein, a hook on the casing for engaging the object to be moved, and a spring means for disengaging the hook operated by the movements of the sheave.

7. A tackle block, comprising a casing, a sheave therein, a hook on the casing for engaging the object to be moved, and means controlled by the movements of the sheave for disengaging the hook.

8. A tackle block, comprising a casing, 21 sheave therein, a hook on the casing for engaging the object to be moved, a spring means connected with the hook, and means operated by the sheave for engaging the Spring means to give pressure to the hook under whieh it will 'oeeonre dieengztged. ii'UIll the olrjeet when relieved ol' the weight thereof.

9. A tackle hlnek, comprising :t easing, it 3 sheave therein, a: hook on the eating for engaging the object to he moved, a. spring means eonneeted with the hook, and :1 rod threaded in the :iein j operated by the ehezwe l'or engaging the spring inez'u'n to give pressure to the hook under Whieh it will heeonie dieeng'ngjed from the nl j =el when relieved of the weight lherenll HP. A tnekle hloek, eonipriwdng :1 easing)", :i sheave therein, :1 hook on the easing for engaging: the ohjeet to he moved, n spring means UUIHl-Lt'tlil with the hook, it rod threaded in the easing, n hevel pinion splined on the rod. and :1 bevel pinion on the eheuve meshing therewith whereby the nioveniei'lts oi the ehenve ('Ullril the turning: of the I'Oli to Feed the rod zigjninet the spring means of the hook for (winning said hook to dinengag'e iron: the ohjeet when relieved oi the Weight thereol.

l engaging the object to he moved, a spring means eonneeted with the hook, a rod threaded in the easing, u hevel pinion splined on the rod, a hevel pinion on the sheave meshing therewith wherehv the movements of the sheave cause the turning of the rod to teed the rod against the spring means of the hook [or causing: said hook to disengage I'rom the ohjeet when relieved of the Weight thereof, there being plain portions of the red at the ends of its threaded. portion for permitting the turning ol' the rod utter it has 'linishell its longitudimil movements, a spring surrounding the rod and a eolhtr on the end adapted to engage the spring near the end of the downwznd movement of the rod to give a pressure to the rod for causing the engagement of its threads With the threads of the casing on the return movement of the sheave.

in testimony whereof, I nliix my signature, in presenee of two W'itHOSSOS.

ART H U R BO UGHARD.

\Vitnesses:

R. S. C. CALDWELL, ANNA F. SOHMIDTBAUER. 

